From Veritas Prep Life Test #5.

Pam and Stanley packed several boxes with reams of paper. While both packed, Pam packed 60% of the total number of boxes. After Pam stopped, Stanley packed the same number of boxes that he had packed while working with Pam. What is the ratio of the number of boxes Pam packed to the number of boxes Stanley packed?

A. 1:4
B. 1:3
C. 3:5
D. 3:4
E. 3:2

Solution is D.

If the ratio is 3:4, with Pam packing less boxes than Stan, how could she have packed 60% of the boxes and Stan packed 40%? I'd chosen E.

Pam only packed 60% of the boxes while she and Stanley were both packing; Stanley continued packing after Pam quit. This means that P:S = 3x:2x when they both worked, but we know that, in total, Stanley packed a total of 4x boxes (2x with Pam and 2x after she finished). This gives a final P:S ratio of 3x:(2x+2x), or 3x:4x.

Bill